Fish and Wildlife monitors
the levels of poly-chlorinated biphenyls (PCBs)1, some chlorinated pesticides, mercury, and lead in the edible
muscle tissue, liver, or whole bodies of fish and crabs. For fish, we
assess exposure to polycyclic aromatic hydrocarbons (PAHs)2 by monitoring the levels of PAH metabolites3 in the fishes' bile. Insufficient funding
is available to monitor dioxins, alkyl phenols and organotins.
The following table lists the chemicals currently monitored and
the detection methods used. Historically, we monitored for the
presence of over 100 compounds but have discontinued monitoring for
compounds not usually detected in the biota or detectable compounds
that may not reflect environmental conditions (e.g., arsenic and copper).

A group of organic compounds. PCB's are highly toxic to aquatic life.
They persist in the environment for long periods of time, and they
are bioaccumulants.

A class of chemicals typically formed by burning
and common in the environment. PAHs are also common to petroleum products
and oil. Although most of these compounds are harmless or mildly toxic,
some are carcinogenic.